PostgreSQL code

Not ours. Everything here is copied from the PostgreSQL tree. It is the base for the 2.1 backport of the stats restore functions, so 16 and 17 can load a dump made by pg_dump 18 or 19. The rest of pg_regresql is BSD-2-Clause; these files stay under the PostgreSQL License.

Provenance

repo      https://github.com/postgres/postgres
branch    REL_18_STABLE
commit    780900dcfab (2026-11-09)

src/backend/statistics/relation_stats.c   -> relation_stats.c
src/backend/statistics/attribute_stats.c  -> attribute_stats.c
src/backend/statistics/stat_utils.c       -> stat_utils.c
src/include/statistics/stat_utils.h       -> stat_utils.h

158c761 imported them from 1370a7832a2 (2026-10-07). bf52896 moved them to 780900dcfab. The only upstream change in between is 780900dcfab (2026-11-09), CVE-2026-116329: hold the target relation open while the attribute input is parsed, and re-check the column before writing. Nothing else in these four files changed on REL_18_STABLE in that window.

Local changes

The port commit is the diff worth reading:

git diff bf52896..<port-commit> -- pg_ext/restore

Each .c file is wrapped in

#if PG_VERSION_NUM >= 160000 && PG_VERSION_NUM < 180000

so 14 and 15 keep building (empty objects) and 18+ is unaffected. On 16/17 the two functions are real.

Every non-static symbol got a regresql_ prefix. It is cheap, and it stops a server fork that exports the same names from colliding with us. PG_FUNCTION_INFO_V1 went on the two entry points only.

statistics/stat_utils.h does not exist on 16/17, so the local stat_utils.h is included instead. On 16 attribute_stats.c also needs utils/typcache.h and nodes/miscnodes.h (17 and 18 happen to get them transitively), and stat_utils.c needs catalog/objectaddress.h for get_relkind_objtype.

The ownership check had to be split. ACL_MAINTAIN is 17+, and pg_class_ownercheck was removed in 16. So 17 uses pg_class_aclcheck(…, ACL_MAINTAIN), 16 falls back to object_ownercheck(RelationRelationId, …), and the database owner bypasses both.

relallfrozen exists only on 18+. The kwarg stays in relarginfo so a dump that passes it is still accepted and type-checked, but the value is dropped, there is no column to put it in. That also shrinks the update arrays from 4 to 3.

pg_clear_relation_stats and pg_clear_attribute_stats are gone, together with cleararginfo and delete_pg_statistic, which only the clear function called. init_empty_stats_tuple stays because attribute_statistics_update uses it.

Extended statistics are a separate problem and are not ported here.

Otherwise the bodies are upstream, tabs and all.

Re-syncing

Copy the four files from a newer REL_18_STABLE, commit that as a vendor commit, then rebase the port commit on top. A plain patch will not apply if upstream touched the same functions, so let git do a 3-way merge (git apply -3, or rebase/cherry-pick). Conflicts stay in this directory.

License

The copied files retain their upstream copyright notices and are distributed under the PostgreSQL License. The rest of pg_regresql remains under its BSD 2-Clause license.

PostgreSQL Database Management System
(also known as Postgres, formerly known as Postgres95)

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